Method and apparatus for encoding channel quality indicator and precoding control information bits

ABSTRACT

A method and apparatus for encoding channel quality indicator (CQI) and precoding control information (PCI) bits are disclosed. Each of the input bits, such as CQI bits and/or PCI bits, has a particular significance. The input bits are encoded with a linear block coding. The input bits are provided with an unequal error protection based on the significance of each input bit. The input bits may be duplicated based on the significance of each input bit and equal protection coding may be performed. A generator matrix for the encoding may be generated by elementary operation of conventional basis sequences to provide more protection to a most significant bit (MSB).

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional application Nos.60/827,829 filed Oct. 2, 2006, 60/855,682 filed Oct. 30, 2006,60/884,116 filed Jan. 9, 2007, 60/887,829 filed Feb. 2, 2007, 60/888,272filed Feb. 5, 2007, 60/888,867 filed Feb. 8, 2007, 60/889,038 filed Feb.9, 2007, and 60/895,093 filed Mar. 15, 2007, which are incorporated byreference as if fully set forth.

FIELD OF INVENTION

The present invention is related to wireless communication systems.

BACKGROUND

In the conventional third generation partnership project (3GPP) wirelesscommunication systems, the downlink data channel, (i.e., high speeddownlink shared channel (HS-DSCH)), may carry different amounts of datausing different spreading codes and different modulation and codingschemes (MCSs). The amount of data that can be delivered to a userequipment (UE) over the HS-DSCH depends in part on the downlink channelquality. The UE reports the downlink channel quality to a Node-B using achannel quality indicator (CQI). The Node-B schedules the downlinktransmissions based on the CQI reported by the UE.

For generation of the CQI, the UE performs channel quality measurements.The channel quality measurements are converted into a CQI value.Conventionally, a CQI value between 1 and 31 is generated using a lookuptable. This CQI value is then encoded into CQI bits that are sent overthe uplink channel by the UE.

Multiple-input multiple-output (MIMO) is a scheme that both the UE andthe Node-B use more than one antenna in transmission and reception. WhenMIMO is implemented, multiple data streams may be transmitted betweenthe UE and the Node-B and the UE may need to report multiple CQI valuesto the Node-B. In addition to the CQI, the UE also sends precodingcontrol information (PCI) to instruct the Node-B as to preferences fordownlink preceding.

When in a non-MIMO mode, the UE sends a five (5) bit CQI to the Node-B.The CQI bits are encoded using a (20, 5) code. When in a MIMO mode, theUE may send two types of information to the Node-B. Type-A informationis for support of two streams and type-B information is for support of asingle stream. Type-A information currently requires ten (10)information bits: two (2) for PCI and eight (8) for CQI values, (e.g.,four (4) CQI bits for each stream). Type-B information requires seven(7) information bits: five (5) for CQI and two (2) for PCI. Differentbit combinations may be used, but generally type-A information requiresmore bits than type-B information. Type A and B information areinterspersed in uplink transmission as instructed by the network.

The CQI bits in a non-MIMO mode, and type A and type B information bitsare block coded using (20, 5), (20, 10), and (20, 7) codes,respectively, to a total 20 coded bits using a generator matrixincluding a plurality of basis vectors. A linear (20, 10) code with aminimum distance of 6 is currently used for the type A information. Thebasis sequences for encoding type A information is shown in Table 1. Thebasis sequences for the type-B code are a subset of the basis sequencesfor the type-A code. For type B information, a linear combination of thefirst seven (7) basis sequences of the (20, 10) code is used for a (20,7) code which also results in a minimum distance of 6 that is not thelowest that can be found for a (20, 7) code.

TABLE 1 i M_(i, 0) M_(i, 1) M_(i, 2) M_(i, 3) M_(i, 4) M_(i, 5) M_(i, 6)M_(i, 7) M_(i, 8) M_(i, 9) 0 [1] [0] [0] [0] [0] [0] [0] [0] [0] [0] 1[0] [1] [0] [0] [0] [0] [0] [0] [0] [0] 2 [0] [0] [1] [0] [0] [0] [0][0] [0] [0] 3 [0] [0] [0] [1] [0] [0] [0] [0] [0] [0] 4 [0] [0] [0] [0][1] [0] [0] [0] [0] [0] 5 [0] [0] [0] [0] [0] [1] [0] [0] [0] [0] 6 [0][0] [0] [0] [0] [0] [1] [0] [0] [0] 7 [0] [0] [0] [0] [0] [0] [0] [1][0] [0] 8 [0] [0] [0] [0] [0] [0] [0] [0] [1] [0] 9 [0] [0] [0] [0] [0][0] [0] [0] [0] [1] 10 [1] [0] [0] [0] [1] [0] [1] [1] [1] [1] 11 [1][1] [0] [0] [0] [1] [0] [1] [1] [1] 12 [0] [1] [1] [0] [0] [0] [1] [0][1] [1] 13 [1] [0] [1] [1] [0] [0] [0] [1] [0] [1] 14 [1] [1] [0] [1][1] [0] [0] [0] [1] [0] 15 [1] [1] [1] [0] [1] [1] [0] [0] [0] [1] 16[1] [1] [1] [1] [0] [1] [1] [0] [0] [0] 17 [0] [1] [1] [1] [1] [0] [1][1] [0] [0] 18 [1] [0] [1] [1] [1] [1] [0] [1] [1] [0] 19 [0] [1] [0][1] [1] [1] [1] [0] [1] [1]

Since the CQI and PCI bits are transmitted to the Node-B without acyclic redundancy check (CRC), the transmitted CQI bits may beincorrectly received. Consequently, incorrect CQI bits may be used forthe downlink scheduling by the Node-B, which results in system capacitydegradation. Unlike errors in other decoding, the size of the errormatters in CQI decoding. The CQI value ranging from 1 to 31 is mapped toCQI values, an error in a most significant bit (MSB) would generate abigger error than an error in a non-MSB. Conventional codes are designedto minimize the occurrence of any errors and do not necessarily minimizethe average ‘size’ of the errors.

Therefore, it would be desirable to use codes that minimize the size ofthe errors. In addition or alternatively, a better code with a higherminimum distance and weight would improve the detection probability oftype-B information.

SUMMARY

A method and apparatus for encoding CQI and PCI bits are disclosed. Eachof input bits, such as CQI bits and/or PCI bits, has a particularsignificance. The input bits may be encoded with a linear block coding.The input bits are provided with an unequal error protection based onthe significance of each input bit. The input bits may be duplicatedbased on the significance of each input bit and equal protection codingmay be performed. A generator matrix for the encoding may be generatedby elementary operation of conventional basis sequences to provide moreprotection to an MSB.

BRIEF DESCRIPTION OF THE DRAWINGS

A more detailed understanding may be had from the following descriptionof a preferred embodiment, given by way of example and to be understoodin conjunction with the accompanying drawings wherein:

FIG. 1 is a block diagram of an example WTRU;

FIG. 2 is a block diagram of an example Node-B;

FIG. 3 shows throughput comparison between the conventional 3GPP CQIcode and the above code modified in just one bit of its generatormatrix;

FIG. 4 shows an RMS error performance comparison between an unequalerror protection code and a maximum minimum Hamming distance code; and

FIGS. 5-12 show simulation results for the coding scheme disclosedherein.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

When referred to hereafter, the terminology “wireless transmit/receiveunit (WTRU)” includes but is not limited to a user equipment (UE), amobile station, a fixed or mobile subscriber unit, a pager, a cellulartelephone, a personal digital assistant (PDA), a computer, or any othertype of user device capable of operating in a wireless environment. Whenreferred to hereafter, the terminology “base station” includes but isnot limited to a Node-B, a site controller, an access point (AP), or anyother type of interfacing device capable of operating in a wirelessenvironment.

It should be noted that although the following description referencesthe specific application of CQI and/or PCI, the coding scheme of thepresent invention is applicable to coding any information. It shouldalso be noted that specific dimension of the generator matrices aregiven only as an example, not as a limitation, and the exactpresentation of the code depends on the bit placement of PCI and CQI.

FIG. 1 is a block diagram of an example WTRU 100. The WTRU 100 mayinclude a data generator 102, an encoder 104 and a transmitter 106. Itshould be noted that FIG. 1 shows only a transmit branch for simplicityand the WTRU 100 may further include any conventional processingcomponents including a receiver and components in a receive branch. Thedata generator 102 may include a CQI generator 108 and/or a PCIgenerator 110. The CQI generator 108 generates at least one set of CQIbits. The PCI generator 110 generates PCI bits. The data generator 102generates either CQI bits only, or type A or type B CQI/PCI bits. TheCQI bits or the type A or type B CQI/PCI bits are encoded by the encoder104. The detailed encoding schemes will be explained in detail below.The encoded CQI bits or CQI/PCI bits are transmitted by the transmitter106.

FIG. 2 is a block diagram of an example Node-B 200. The Node-B 200 mayinclude a receiver 202, a decoder 204 and a scheduler 206. It should benoted that FIG. 2 shows only a receive branch for simplicity and theNode-B 200 may further include any conventional processing componentsincluding a transmitter and components in a transmit branch. Thereceiver 202 receives the encoded CQI bits or CQI/PCI bits from the WTRU100. The decoder 204 decodes the encoded CQI or CQI/PCI bits to recoverthe CQI and/or PCI bits. The recovered CQI bits and/or PCI bits are usedby the scheduler 206 for scheduling the next transmission to the WTRU100.

In accordance with one embodiment, the error protection of the inputbits is given in accordance with significance of each of the bits suchthat the most error protection is given to an MSB and a least protectionis given to a least significant bit (LSB). The input bits can be thoughtof as a bit vector. For example, the range of the CQI value is 1 to 31,the CQI value is converted into 5 bit vector, b=[b₀, . . . , b₄], whereb₀ is the MSB and b₄ is the LSB. It should be noted that the position ofthe MSB and the LSB may be opposite. The linear block coding may bedescribed by an n×k generator matrix, where k is the number of inputbits, (e.g., 5 CQI bits, 8 CQI bits and 2 PCI bits, or 5 CQI bits and 2PCI bits), and n is the number of output bits, (e.g., 20 bits). The kinput bits are multiplied by the generator matrix to produce an n-bitcodeword as follows:c=mG;  Equation (1)where c is the output codeword, m is the input vector and G is thegenerator matrix.

Each one of the output bits (elements in c) can be thought of aparity-check on a subset of bits in m. Which bits “participate” in eachone of the parity check is determined by G. The more parity checks aparticular bit participates in, the more redundancy is generated from itand the better protected it will be.

The input bits are ordered in descending or ascending need ofprotection. A list of k positive integers m₀, . . . m_(k-1), isgenerated such that:n≧m₀≧ . . . ≧m_(k-1)≧1.  Equation (2)The generator matrix G is then generated as follows: the row of Gcorresponding to b_(i), (i.e., row i+1), is populated with m_(i) 1's andthe rest of the entries are 0's. Thus, the input bits participate inprogressively less and less parity checks and therefore incurprogressively less error protection.

This method reduces the probability of large errors at the expense ofthe probability of much smaller errors which are insignificant to systemperformance. This offers substantial freedom in the design of the codeand depending on the specific placement on 1's a code may turn out to begood or bad. In particular, the matrix G should remain full row-rank.The minimum number of 1's in any non-zero linear combination of the rowsmay be minimized. A pseudo-random code design is likely to result in agood code especially as block length increases. For very large lengthssuch codes are a sub-family of irregular low density parity check (LDPC)codes. Two alternative 5×20 generator matrix examples for theconventional CQI configuration are shown below (the MSB in the inputvector is the leftmost bit and the LSB is the rightmost bit in thisexample).

GENERATOR MATRIX EXAMPLE 1

$\begin{matrix}1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 \\1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 \\1 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 0 \\1 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 0 & 0 \\1 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0\end{matrix}.$

GENERATOR MATRIX EXAMPLE 2

$\begin{matrix}1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 \\1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 \\1 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 0 & 0 \\1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 \\1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0\end{matrix}.$

The WTRU 100 may need to transmit two or more CQI values that pertain toa single stream or to two or more MIMO streams. In such a case, the WTRU100 generates multiple CQI values and maps the CQI values to multiplesequences of CQI bits. For example, the WTRU 100 may generate three CQIsincluding one CQI for a single stream case and two CQIs for a two streamcase. One of the CQI bits, (e.g., the single stream CQI bits), isdenoted as a primary sequence (P), and the others are denoted assecondary sequences, (e.g., S′1 and S′2). Then, the primary and thesecondary sequences are concatenated for coding according to the abovecoding scheme, (i.e., the input to the encoder 104 is defined as m=[PS′1 S′2]). Alternatively, the primary sequence and the secondarysequences may be combined, (e.g., S1=S′1-P and S2=S′2-P) andconcatenated to be input into the encoder 104, (e.g., m=[P S1 S2]).Either way, the rows in the generator matrix should reflect the factthat the weights of the bits of m are now not exponential, although theweight of its components is.

Alternatively, the input bits may be unequally duplicated and then codedusing an equal protection code, such as Reed-Muller (RM) code.

The CQI bits may be concatenated with acknowledgement information. Inthe 3GPP frequency division duplex (FDD) Release 6 standard, the highspeed uplink control channel (HS-DPCCH) is constructed such that thefirst two time slots carry CQI information and the third time slotcarries acknowledgement information, (i.e., positive acknowledgement(ACK) or negative acknowledgement (NACK)). Since the WTRU 100 usuallygenerates a CQI value based on channel estimation prior to the CRC checkon the received data block, the WTRU 100 may transmit the CQI first, andthen transmit the ACK/NACK so that the latency in the link adaptationcan be reduced. In order to preserve this advantage while using anunequal error protection coding scheme, the CQI bits and acknowledgementbits are concatenated and encoded as follows:c=mG=[m_(CQI)m_(Ack)]G;  Equation (3)where m_(CQI) is CQI bits, m_(Ack) is acknowledgement information, and Gis a generator matrix. For example, m_(CQI) is a 1×5 row vector, m_(Ack)is one bit for a single scream (in general 1×m row vector for mstreams), and G is a 6×30 matrix with the first 20 elements in the lastrow being 0s.

This embodiment may be extended to encode a set of multiple codes whichrequire different transmit time as follows:

$\begin{matrix}{\lbrack {{\overset{arrow}{c}}_{1},{\overset{arrow}{c}}_{2},{\ldots\mspace{20mu}{\overset{arrow}{c}}_{N}}} \rbrack = {{\lbrack {{\overset{arrow}{m}}_{1},{\overset{arrow}{m}}_{2},{\ldots\mspace{14mu}{\overset{arrow}{m}}_{M}}} \rbrack\begin{bmatrix}G_{11} & G_{12} & \ldots & G_{1N} \\0 & G_{22} & \ldots & G_{2N} \\0 & 0 & \ddots & \vdots \\0 & 0 & \ldots & G_{MN}\end{bmatrix}}.}} & {{Equation}\mspace{14mu}(4)}\end{matrix}$

In accordance with another embodiment, the conventional 3GPP type A ortype B code is changed by moving one or more bits in the generatormatrix to improve the performance. The basis sequences for the new (20,5) code generated in this way are shown in Table 2. The code is based onthe conventional 3GPP (20,5) code in the non-MIMO mode. In Table 2, thefifth column corresponds to the MSB and the fourth column corresponds tothe next MSB. The bit ‘1’ in the fifth column and 20th row is changed to‘0’ and the bit ‘0’ in the fourth column and 20th row is changed to ‘1’to give more protection to the next MSB at the expense of the MSBprotection.

TABLE 2 i M_(i, 0) M_(i, 1) M_(i, 2) M_(i, 3) M_(i, 4) 0 1 0 0 0 1 1 0 10 0 1 2 1 1 0 0 1 3 0 0 1 0 1 4 1 0 1 0 1 5 0 1 1 0 1 6 1 1 1 0 1 7 0 00 1 1 8 1 0 0 1 1 9 0 1 0 1 1 10 1 1 0 1 1 11 0 0 1 1 1 12 1 0 1 1 1 130 1 1 1 1 14 1 1 1 1 1 15 0 0 0 0 1 16 0 0 0 0 1 17 0 0 0 0 1 18 0 0 0 01 19 0 0 0 1 0

FIG. 3 shows throughput comparison between the conventional 3GPP CQIcode and the code in Table 2. FIG. 3 show the performance improvementwith the new code.

The generator matrix in Table 2 or its variance may be generated bystarting with a maximum minimum Hamming distance code of a size somewhatsmaller than the desired code. For example, if a (20, 5) code isdesired, a maximum minimum Hamming distance code of size (17, 5), (i.e.,5×17 generator matrix), is first found. Once the 5×17 generator matrixis found, the size of the generator matrix is extended by adding a 5×3matrix Z of zeros to the 5×17 generator matrix. Thereafter, some or allof the zeros in the p-th row of the Z matrix are set to ‘1’, where pcorresponds to the position of the MSB in the data being encoded. Thismakes the distance between codewords with MSB=1 and those with MSB=0larger, (i.e., more protection to the MSB). If not all elements in row pare set to ‘1’, then the element in row q and in column that is not setto ‘1’ in p-th row is set to ‘1’ where q corresponds to the position ofthe next MSB in the data being encoded. In this way, the more importantbits are better protected. However, it comes at the cost of having aminimum distance set by the smaller (n,k) code.

Generator Matrix Example 3 for an (20, 8) unequal error protection codegenerated in the similar way is shown below. The generator matrixexample 3 is generated from a (17,8) maximum minimum Hamming distancecode. The right most 8×3 submatrix is added to the 8×17 matrix. In thisexample, the first row corresponds to the MSB and the second rowcorresponds to the next MSB. All elements of the submatrix are zeros,except the first row and the element in the second row and the lastcolumn for better protection of the next MSB.

GENERATOR MATRIX EXAMPLE 3

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 0 & 1 & 1 & 0 & 0 & 1 & 1 & 1 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 1 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 0 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 1 & 1 & 0 & 1 & 0 & 0 & 0 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 0 & 1 & 0 & 1 & 0 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 0 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 1 & 1 & 1 & 0 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 0 & 0 & 0\end{matrix}.$

FIG. 4 shows an RMS error performance comparison between an unequalerror protection code constructed in accordance with this embodiment anda maximum minimum Hamming distance code. The RMS error is better for theunequal error protection code in accordance with this embodiment thanthe maximum minimum Hamming distance code in the region of interest.

In current 3GPP standards, type A information is coded with (20, 10)code and type B information is coded with a (20, 7) code which is asubset code of the (20, 10) code for the type A information. A subsetcode refers to the case where the basis vectors of the (20, 7) code area subset of the basis vectors of the (20, 10) code.

In accordance with one embodiment, a non-subset, linear (20, 7) code isused for type B information and the conventional type A informationcoding (the (20, 10) coding specified in the current 3GPP standards) isused for type A information. The non-subset (20, 7) code may be thesubset (20, 7) code of the conventional (20, 10) code with one (or more)bit flipping. The minimum distance of the (20, 7) code is eight (8). Thenon-subset (20, 7) code is generated such that the weight distributionof the code is non-optimal and the code offers better protection to theMSB of the CQI value. A generator matrix example 4 for this embodimentis shown below (in this example, the MSB in the input vector is therightmost bit and the LSB is the leftmost bit).

GENERATOR MATRIX EXAMPLE 4

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 1 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 0 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 1 & 0 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 0 & 0 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1\end{matrix}.$

A better protection of the MSB of CQI bits reduces the probability oflarge magnitude errors in CQI at the Node-B at the expense of a slightlyhigher probability of error. Both PCI errors and small magnitude CQIerrors have a small impact on system performance while large magnitudeCQI errors have a significant impact. Therefore, better error protectionprovided to the MSB of CQI bits is advantageous.

In accordance with another embodiment, a non-subset (20, 7) linear codethat has a minimum distance of 8 is used and equal error protection isprovided for type B information, and the conventional type A informationcoding (the (20, 10) coding specified in the current 3GPP standards) isused for type A information. One way of generating this non-subset (20,7) code is to start with a good smaller code and search for extensions.A generator matrix example 5 for this embodiment is shown below (in thisexample, the MSB in the input vector is the rightmost bit and the LSB isthe leftmost bit).

GENERATOR MATRIX EXAMPLE 5

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 1 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 0 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 1 & 0 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 0 & 0 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1\end{matrix}.$

In accordance with another embodiment, for the case where CQI and PCIuse 4 and 2 bits, respectively, approximately equal error protectioncode is used for type B information coding and the conventional type Ainformation coding is used for type A information. A (20, 6) generatormatrix example 6 for this embodiment is given below (in this example,the MSB in the input vector is the rightmost bit and the LSB is theleftmost bit).

GENERATOR MATRIX EXAMPLE 6

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 \\0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 1 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 0 & 1 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 1 \\0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1\end{matrix}.$

In accordance with another embodiment, type B input bits are unequallyduplicated before encoding. There are many variations on this scheme inwhich one or more of the CQI MSBs and/or some or all of the PCI bits areemphasized to create a 10-bit input to the (20, 10) encoder used fortype A information coding. For example, the MSB of type B CQI may berepeated 3 times. Note that this is still a (20, 7) code with agenerator matrix that can be constructed from linear combinations of thebasis vectors of the generator matrix of the (20, 10) code.

In accordance with another embodiment, both type A and type B codes arechanged from the conventional code and the type B code is a subset codecomprising the first 7 columns of the type A code. A new type Agenerator matrix is created from the conventional (20, 10) generatormatrix by using elementary column operations, (such as a column isaltered by adding one other column to it). It is well known that theseoperations do not lead to codewords that are not also part of theoriginal code. They do, however, enable construction of a better type Bsubset code.

The appropriate type B code can be determined in terms of its separationvector. For a linear (n,k) binary code C, the separation vector (SV)s(G)=(s(G)₁, . . . , s(G)_(k)) of length k with respect to a generatormatrix G of C is defined by:s(G)_(i)=min{wt(mG)|mεGF(2)^(k) ,m _(i)≠0},i=1, . . . , k.  Equation (5)

It is generally understood that the value of an element of the SVcorresponds to the protection that is given to the correspondinginformation bit akin to minimum distance properties of codes in general.Thus, for approximately equal error protection code, all the elements ofthe separation vector are equal. By finding codes with unequal elementvalues, it is possible to protect better some desired information bits.Specifically, if a code is found that has min_(i)(s(G)_(i))≧6 withlarger elements for the MSB of CQI bits, then this code is animprovement over the conventional type B coding without changing theproperties of type A code.

For example, this code may be obtained by the following operations:

1) The 5th column basis sequence is replaced by the XOR operation ofcolumn 5 and column 8;

2) The 6th column basis sequence is replaced by the XOR operation ofcolumn 6 and column 9; and

3) The 7th column basis sequence is replaced by the XOR operation ofcolumn 7 and column 10.

The generator matrix obtained in this way (in a transpose form) withseparating vector of s(G1)=(7, 6, 6, 6, 7, 7, 7) is shown below.

GENERATOR MATRIX EXAMPLE 7

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 \\1 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 1 \\1 & 1 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 1 \\0 & 1 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 \\1 & 0 & 1 & 1 & 1 & 0 & 1 & 1 & 0 & 1 \\1 & 1 & 0 & 1 & 1 & 1 & 0 & 0 & 1 & 0 \\1 & 1 & 1 & 0 & 1 & 1 & 1 & 0 & 0 & 1 \\1 & 1 & 1 & 1 & 0 & 1 & 1 & 0 & 0 & 0 \\0 & 1 & 1 & 1 & 0 & 0 & 1 & 1 & 0 & 0^{\bullet} \\1 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 1 & 0 \\0 & 1 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 1\end{matrix}$

Further coding examples may be obtained by permutation of the abovecodes or by starting with a smaller code and searching for the bestextensions. Further generator matrix examples are provided herein.

GENERATOR MATRIX EXAMPLE 8

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 1 & 1 & 0 & 0 & 0 & 0 & 1 & 1 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 1 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 1 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 1 & 1 & 0 & 0 & 0 & 0 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 1 & 0 & 0 & 0 & 1 & 1 & 1 & 0\end{matrix}.$

GENERATOR MATRIX EXAMPLE 9

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 \\0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 1 & 1 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1\end{matrix}.$

GENERATOR MATRIX EXAMPLE 10

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 1 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 1 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 1 & 0 & 1 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 1 & 0 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 1 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 0 & 0 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 0 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 1 & 1 & 1 & 0 & 1 & 1 & 1 & 0\end{matrix}.$

GENERATOR MATRIX EXAMPLE 11

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 \\0 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 0 & 0 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 \\0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1\end{matrix}.$

GENERATOR MATRIX EXAMPLE 12

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1\end{matrix}.$

GENERATOR MATRIX EXAMPLE 13

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1\end{matrix}.$

GENERATOR MATRIX EXAMPLE 14

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1\end{matrix}.$

Further subset coding examples may be created in the following manner.First, the ‘best’ type A code is identified. For example, for the(20,10) codes, it is known that there are 1,682 non-equivalent maximalminimum distance linear binary (20,10,6) codes having a minimum distanceof six (6). A maximal (n,k) minimum distance code is a code thatachieves the theoretical maximum minimal distance between all pairs ofcodewords. Among these codes, codes with a lowest block error rate(BLER) are found. The BLER may be computed from its weight distribution.For the case of the (20,10) codes, the best code in the state of the artis unique and easily identified as it has a minimum distance of six (6)and the fewest number of minimum distance codewords (40) by a largemargin. When looking for a good subset code, it is only needed toinvestigate the (20,10,6,40) codes from which to draw a subset code.

By taking an (n,k) code and applying any sequence of elementaryoperations, other codes are created whose codewords are either the sameas the original codewords of (n,k) code, which makes the codesequivalent, or a smaller subset of those codewords. The codes withsmaller subsets of codewords are degenerate and are not worthinvestigation. The others are potential candidates to be used to createa subset code.

For a (n,k) type A code, all sequences of elementary operations may berepresented as a pre-multiplying k×k matrix of 1's and 0's to thegenerator matrix. The pre-multiplying matrix is called a translationmatrix, (e.g., 10×10 or alternatively 7×10). The translation matrix maybe generated deterministically or randomly. Each of these subset codesare then checked for good properties, such as achieving max mindistance, counting the number of minimum weight codewords, andcomputation of the separation vector.

For all (20,10) coding examples, there are many bit mappingpossibilities that may result in different coding properties. Forexample, there may be two CQI values of four (4) bits each mapped aspci0, pci1, cqi1_0, cqi1_1, cqi1_2, cqi1_3, cqi2_0, cqi2_1, cqi2_2,cqi2_3, where cqi1_3 and cqi2_3 are MSBs. This sequence is mapped torows 1:10 of the generating matrix. Alternatively, the sequence may bemapped to rows 10:1 of the generator matrix in reverse order.

Alternatively, the two four bit CQI values may be combined into a singleeight bit CQI composite (CQIC). For example, it has been proposed thatCQIC={15*CQI1+CQI2+31} for two streams, and {SingleCQI} for one stream.CQI1 and CQI2 have 15 possible values each and SingleCQI has 30 possiblevalues. Then, cqic7, cqic6, cqic5, cqic4, cqic3, cqic2, cqic1, pci1,pci0, cqic0 may be applied to rows 1:10 of the generator matrix, oralternatively 10:1 in reverse order. For type B (20, 7) coding, cqi4,cqi3, cqi2, cqi1, cqi0, pci1, pci0 may be mapped to rows 1:7, oralternatively 7:1 in reverse order. A generator matrix example 15obtained in this way is shown below.

GENERATOR MATRIX EXAMPLE 15

$\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 1 & 0 & 1 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 1 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 1 & 0 & 0 & 1 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 1 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 0 & 0 & 1 & 0 & 1 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1 & 1 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 0 & 1\end{matrix}.$

Type B PCI/CQI information coding results in lower transmitted powerrequirements due to different coding rate and coding gain. Such lowertransmit power is desirable as it lowers the average uplinkinterference. Type A power level is currently determined by the networkas a multiple of an uplink reference channel, (i.e., dedicated physicalcontrol channel (DPCCH). In accordance with the embodiments disclosedherein, different transmission powers are used for type A and type Binformation. Both type A and type B power may be independently defined,(i.e., as power multiplier or addition in dBs), in terms of the power ofanother channel. The multipliers or additions are provided by thenetwork. The reference channel may be downlink channel or uplinkchannel. The downlink reference channel may be common pilot channel(CPICH), primary common control physical channel (P-CCPCH),synchronization channel (SCH), high speed shared control channel(HS-SCCH) or any other channel. The power of some of these channels maybe defined in terms of power of other channels. The uplink referencechannel may be DPCCH, enhanced uplink DPCCH (E-DPCCH), random accesschannel (RACH) (after ACK/NACK) or any other channel. Likewise, thepower of some of these channels may be defined in terms of power ofother channels.

After CQI bits are spread to the chip rate, the real-valued spreadsignals are weighted by a gain factor. The gain factor β_(hs) for theCQI bits on the HS-DPCCH is derived from the quantized amplitude ratio(A_(hs)=β_(hs)/β_(c)), which is translated from Δ_(CQI) signaled by ahigher layer. β_(c) is the gain factor for the DPCCH. The translation ofΔ_(CQI) into the quantized amplitude ratio A_(hs) is shown in Table 3.

TABLE 3 Quantized amplitude ratios Signalled values for Δ_(CQI) A_(hs) =β_(hs)/β_(c) 9 38/15 8 30/15 7 24/15 6 19/15 5 15/15 4 12/15 3  9/15 2 8/15 1  6/15 0  5/15

For HS-DPCCH slots carrying CQI bits, if the WTRU is not configured inMIMO mode, A_(hs) equals the quantized amplitude ratio translated fromthe signaled value Δ_(CQI). If the WTRU is configured in MIMO mode,A_(hs), equals the quantized amplitude ratio translated from thesignaled value Δ_(CQI) when a CQI of type B is transmitted, and A_(hs)equals the quantized amplitude ratio translated from the signaled valueΔ_(CQI)+1 when a CQI of type A is transmitted.

Alternatively, once one of the type A or type B power is defined asexplained above and transmission power for the other type may bedetermined as a network provided multiplier or dB addition or may becomputed from the defined one based on a pre-defined formula. Forexample, type B power may be computed by the WTRU using a look up table(LUT_(A)). The LUT_(A) may be used to compute type A power from an indexΔ_(CQI) signaled by the network. Given Δ_(CQI), type B power may becomputed using a separate lookup table LUT_(B) that implements thefunction P_(B)=LUT_(B) (Δ_(CQI)). An example LUT_(B) is shown in Table4.

TABLE 4 Quantized amplitude ratios Signalled values for Δ_(CQI) A_(hs) =β_(hs)/β_(c) 8 21/15  7 17/15  6 14/15  5 11/15  4 9/15 3 7/15 2 6/15 15/15 0 5/15

Alternatively, a function g that operates on Δ_(CQI) may be used tocreate an input to LUT_(A) thus keeping the same set of power levelsthat are used for type A. This operation may be described asP_(B)=LUT_(A) (g(Δ_(CQI))). The function g may itself be implemented asa lookup table. For example, g(Δ_(CQI))=maximum(0, g(Δ_(CQI))−1).

FIG. 5 shows an individual bit error rate using the generator matrixexample 4. It shows that the MSB of CQI bits (cqi4) is about 0.6 dBbetter than the rest PCI/CQI bits. As a reference, the bit error rate ofthe conventional coding scheme (labeled as “pcicqi in [1]”) is alsoplotted. The BER measurement using the generator matrix example 4 isabout 0.8 dB better than the conventional coding scheme. FIG. 6 shows ablock error rate (BLER) for the conventional type B 7-bit PCI/CQI andthe coding using the fourth generator matrix example. At 1% BLER, thereis about a 0.8 dB difference in coding again. FIG. 7 shows BLER vs. thecoded bit signal-to-noise ratio (SNR) for the conventional type A 10 bitPCI/CQI, conventional type B 7-bit PCI/CQI and the coding using thefourth generator matrix example. For comparison between the type A andtype B reporting formats, the power required at 1% BLER for type APCI/CQI format is about 1.5 dB higher than the one using the generatormatrix example 8 for type B. FIG. 8 is a plot of CQI mean square error(MSE) measurement in two type B coding schemes. For the same amount ofMSE errors, there is about >1 dB in SNR required.

FIGS. 9-12 show performance comparisons for conventional coding and thecoding using the fifth and/or the seventh generator matrix examples.Note that in FIGS. 9-12, “[1]” refers to prior art for type-B, “optimalEEP” represents the case using the fifth generator matrix example, and“G1” represents the case using the seventh generator matrix example.FIG. 9 shows that type-A matrix transformation does not change the BLERof type-A code. FIG. 10 shows a comparison for PCI BLER for prior arttype-B code, the case using the fifth generator matrix example and thecase using the seventh generator matrix example. FIG. 11 shows agraphical comparison of CQI BLER for the prior art type-B code, the caseusing the fifth generator matrix example and the case using the seventhgenerator matrix example.

FIG. 12 shows comparison of CQI standard deviation, (computed as rootmean square error (RMSE)), for prior art type-B coding, and the caseusing the fifth generator matrix example and the case using the seventhgenerator matrix example. As can be seen in FIGS. 9-12, both the fifthand the seventh generator matrix examples perform better than the priorart.

Although the features and elements are described in the embodiments inparticular combinations, each feature or element can be used alonewithout the other features and elements of the embodiments or in variouscombinations with or without other features and elements of theembodiments. The methods or flow charts provided may be implemented in acomputer program, software, or firmware tangibly embodied in acomputer-readable storage medium for execution by a general purposecomputer or a processor. Examples of computer-readable storage mediumsinclude a read only memory (ROM), a random access memory (RAM), aregister, cache memory, semiconductor memory devices, magnetic mediasuch as internal hard disks and removable disks, magneto-optical media,and optical media such as CD-ROM disks, and digital versatile disks(DVDs).

Suitable processors include, by way of example, a general purposeprocessor, a special purpose processor, a conventional processor, adigital signal processor (DSP), a plurality of microprocessors, one ormore microprocessors in association with a DSP core, a controller, amicrocontroller, Application Specific Integrated Circuits (ASICs), FieldProgrammable Gate Arrays (FPGAs) circuits, any other type of integratedcircuit (IC), and/or a state machine.

A processor in association with software may be used to implement aradio frequency transceiver for use in a wireless transmit receive unit(WTRU), user equipment (UE), terminal, base station, radio networkcontroller (RNC), or any host computer. The WTRU may be used inconjunction with modules, implemented in hardware and/or software, suchas a camera, a video camera module, a videophone, a speakerphone, avibration device, a speaker, a microphone, a television transceiver, ahands free headset, a keyboard, a Bluetooth® module, a frequencymodulated (FM) radio unit, a liquid crystal display (LCD) display unit,an organic light-emitting diode (OLED) display unit, a digital musicplayer, a media player, a video game player module, an Internet browser,and/or any wireless local area network (WILAN) module.

1. A method for encoding type B information bits, the method comprising:generating type B information bits including channel quality indicator(CQI) bits and precoding control information (PCI) bits; encoding thetype B information bits using a (20, 7) code to generate an outputcodeword, a minimum distance of the (20, 7) code being eight (8), weightdistribution of the (20, 7) code providing better protection to a mostsignificant bit (MSB) the CQI bits; and sending the output codeword. 2.The method of claim 1 wherein the (20, 7) code is a non-subset code of(20, 10) code for type A information bits.
 3. The method of claim 1wherein the (20, 7) code is a subset code of (20, 10) code for type Ainformation bits with one bit flipping.
 4. The method of claim 1 whereina generator matrix for the (20, 7) code is as follows: $\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 1 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 0 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 1 & 0 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 0 & 0 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1\end{matrix}.$
 5. A wireless transmit/receive unit (WTRU) for encodingtype B information bits, the WTRU comprising: a data generator forgenerating type B information bits including channel quality indicator(CQI) bits and precoding control information (PCI) bits; an encoder forencoding the type B information bits using a (20, 7) code to generate anoutput codeword, a minimum distance of the (20, 7) code being eight (8),weight distribution of the (20, 7) code providing better protection to amost significant bit (MSB) of the CQI bits; and a transmitter forsending the output codeword.
 6. The WTRU of claim 5 wherein the (20, 7)code is a non-subset code of (20, 10) code for type A information bits.7. The WTRU of claim 5 wherein the (20, 7) code is a subset code of (20,10) code for type A information bits with one bit flipping.
 8. The WTRUof claim 5 wherein a generator matrix for the (20, 7) code is asfollows: $\begin{matrix}1 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 1 & 0 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 1 & 0 \\0 & 1 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 \\0 & 0 & 1 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 0 \\0 & 0 & 0 & 1 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 1 & 0 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 1 & 0 & 0 & 1 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 0 \\0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 1 & 0 & 1 & 1 & 1 & 0 & 0 & 1 & 0 \\0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1\end{matrix}.$
 9. A method for encoding channel quality indicator (CQI)bits in a wireless transmit/receive unit (WTRU), the method comprising:generating CQI bits; encoding the CQI bits; applying a gain factorB_(hs) to the CQI bits; and sending the encoded CQI bits, wherein thegain factor β_(hs), for the CQI bits is derived from a quantizedamplitude ratio (A_(hs) =β_(hs)/β_(c)), β_(c) being a gain factor for adedicated physical control channel (DPCCH), and wherein if the WTRU isconfigured in multiple-input multiple-output(MIMO) mode, A_(hs) equalsthe quantized amplitude ratio translated from a signaled value ΔCQI+1when a CQI of type A is transmitted.
 10. The method of claim 9 whereinfor time slots carrying the CQI bits, if the WTRU is not configured inmultiple-input multiple-output (MIMO) mode, A_(hs) equals the quantizedamplitude ratio translated from the signaled value Δ_(CQI).
 11. Themethod of claim 9 wherein for time slots carrying the CQI bits, if theWTRU is configured in multiple-input multiple-output (MIMO) mode, A_(hs)equals the quantized amplitude ratio translated from the signaled valueΔ_(CQI) when a CQI of type B is transmitted.
 12. The method of claim 9,wherein A_(hs) is translated to 38/15 when the signaled value Δ_(CQI+)1equals to
 9. 13. The method of claim 9, wherein β_(hs) is a gain factorfor a high speed dedicated physical control channel (HS-DPCCH).
 14. Awireless transmit/receive unit (WTRU) for encoding channel qualityindicator (CQI) bits, the WTRU comprising: a CQI generator forgenerating CQI bits; an encoder for encoding the CQI bits; and atransmitter for applying a gain factor β_(hs) to the CQI bits andsending the encoded CQI bits, wherein the gain factor β_(hs) for the CQIbits is derived from a quantized amplitude ratio (A_(hs) =β_(hs)/β_(c)),β_(c) being a gain factor for a dedicated physical control channel(DPCCH), and wherein A_(hs) equals to the quantized amplitude ratiotranslated from a signaled value Δ_(CQI+)1 when a CQI of type A istransmitted.
 15. The WTRU of claim 14 wherein for time slots carryingthe CQI bits, if the WTRU is not configured in multiple-inputmultiple-output (MIMO) mode, A_(hs) equals the quantized amplitude ratiotranslated from the signaled value Δ_(CQI).
 16. The WTRU of claim 14wherein for time slots carrying the CQI bits, if the WTRU is configuredin multiple-input multiple-output (MIMO) mode, A_(hs) equals thequantized amplitude ratio translated from the signaled value Δ_(CQI)when a CQI of type B is transmitted.
 17. The WTRU of claim 14, whereinA_(hs), is translated to 38/15 when the signaled value Δ_(CQI+)1 equalsto
 9. 18. The WTRU of claim 14, wherein β_(hs) is a gain factor for ahigh speed dedicated physical control channel (HS-DPCCH).